The invention relates to a folding hood for motor vehicles, and, more particularly, to a folding hood for motor vehicles, having a dimensionally stable rear window, especially of mineral glass. When the hood is closed, the rear window is connected along its lower edge side via a rigidly tensioned tensioning means to a material-retaining hoop forming the lower termination of the hood. When the hood is folded down, the rear window can be folded downwards into a storage position about an axis extending approximately parallel to the lower edge side of the rear window.
Such a folding hood has already been disclosed, for example, in German Patent Document P 41 28 115.2, which is not a prior publication. In this folding hood, the heavy rear window, made from mineral glass, is retained along its lower edge side by a fabric strip of the hood cover and along its upper edge side again by the hood cover together with a plurality of additional straps which are secured to the central tube of the main strut and rest on the corner strut.
In the closed state of the folding hood, the rear window, which is enclosed by a window frame, is thus held exclusively via flexible tensioning means by the adjoining frame members. This has the advantage that the folding hood can be folded very compactly when lowered into the associated hood box, since the bulky rear window can be lowered onto the material-retaining hoop and folded down into a bearing position resting upon the latter. The fabric strip extends under the rear window acting as a film hinge.
However, it is simultaneously necessary to accept the fact that, when the hood is closed and the vehicle is being driven, the rear window is caused to make flapping movements under the influence of air turbulence. These flapping movements, caused by pressure surges against the large-area rear window, not only result in increased mechanical stress in the region of the rear wall of the hood but also, within certain speed ranges, cause intrusive "drumming noises".
There is therefore needed a folding hood of the above-described type improved to the extent that the flapping of the window in the driving operation can be reduced so substantially that it is at least impossible for any intrusive "drumming noises" to arise.
This need is met according to the present invention by a folding hood for motor vehicles, having a dimensionally stable rear window, especially of mineral glass. When the hood is closed, the rear window is connected along its lower edge side via a rigidly tensioned tensioning means to a material-retaining hoop forming the lower termination of the hood. When the hood is folded down, the rear window can be folded downwards into a storage position about an axis extending approximately parallel to the lower edge side of the rear window. A support device is arranged on the material retaining hoop, by which the rear window is supported, close to its lower edge side, transversely to the direction of tension of the tensioning means on the material-retaining hoop, while the folding hood remains closed.
As compared with direct supporting of the rear window, supporting of the support device on the window frame has the advantage that the field of vision of the rear window cannot be restricted by the support device.
Particularly effective supporting of the rear window is achieved if the supporting forces take effect not at isolated points but virtually over the entire width of the rear window.
A proven solution here is an elongate bearing section which can be detachably connected to the material-retaining hoop to serve as a mounting for an additional support section which, for the sake of satisfactory internal damping, preferably consists of rubber or of a comparable elastomeric plastic.
A clip-type seating for the support section permits it to be simply assembled when the bearing section is attached to the material-retaining hoop.
Advantageously, the support section comprises a supporting are which is thickened, in the manner of a bead, and has a convexly rounded support side, as a result of which the supporting force acts substantially at right angles to the plane of the rear window.
By means of the bearing section, differences in curvature between the rear window and the material retaining clip can be concealed in a simple manner, since the line of the support section can be adapted to the curvature of the window.
In order for no additional lining to be necessary for the surfaces of the material-retaining hoop which remain visible from inside, the bearing section is preferably also used as a masking section for these visible surfaces.
The elongate support device can, moreover, advantageously serve to mask screw attachment means on the lower part of the window frame.
By pressing the rubber section onto the window frame with a uniform backward-directed prestress, a particularly durable quietening of the rear window in the driving operation can be achieved.
In what follows, an illustrative embodiment of the invention is explained with reference to an illustrative drawing.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.